import java.util.Arrays;
import java.util.Scanner;

/**
 * Created with Intellij IDEA.
 * Description:
 * User:Lenovo
 * Date:2024-12-11
 * Time:12:42
 */
public class Text {
    public static void main(String[] args) {
        String s = "ab";
        String S = s.toLowerCase();
        char[] arr = S.toCharArray();
        char[] arr2 = new char[arr.length];
        int count = 0;
        for (int i = 0; i < arr.length; i++) {
            if(arr[i]>='a'&&arr[i]<='z'||arr[i]>=48&&arr[i]<=57){
                arr2[count] = arr[i];
                count++;
            }
        }
        int count2 = 0;
        while(count2< arr.length&&arr2[count2]!='\u0000'){
            count2++;
        }
        int left = 0;
        int right = count2-1;
        int flag = 1;
        while(left<right){
            if(arr2[left]!=arr2[right]){
                flag = 0;
                break;
            }
            left++;
            right--;
        }
        if(flag==1){
            System.out.println("true");
        }else{
            System.out.println("false");
        }
    }
}
